Get Life Virus:
Use the Dynawave, as it will get rid of the aura. Hit him, but be careful as it can get blocked by the Ice and Wood attacks. Depending on the attack, change your armor since the Life Virus attacks with elements. The Protoman, M Cannon, and Color Man chips help. Use Projectile chips on the second form, and if you get hit by a bubble it drops use the Energy sub chips (which you should have) and slide under it when it gets close.

Combos
Combine the following chips in order to create the corresponding Program Advance.

Get Needle Man:
Needle Man is a wood type Navi. Use all kinds of swords and blades on him. Fire causes the most damage to him.

Get Guts Man:
Have Roll, Vgun, Shotgun, and Cannons. First use Roll, then let him attack. Dodge it, then use any Shotgun, Vgun, or Cannons. When he attacks again, dodge it then attack. Do this rapidly to win and get the battle chip Gutspunch.

Max out your Dash Attack chips (10). Use them on him when he is on the ground.

Navi Zero Chip
Before battle with Zero, go to the Global Area 1 (where you must go to defeat the Bosses to get the pass codes underneath their warp points for their levels). When you get to Global Area 1, look towards the bottom left. You will see a giant yellow data there. Go there and get it. You will have to take the path under the green Navi that tells you that the Undernet is ahead. When you get the data, Mega Man will tell Lan that this data is hard to read. Lan will then send it to his dad for research. Advance with the story until you get to Zero. When you get to Zero and defeat him, there will be a lot of dialog. Lan's dad will appear, saying that the mystery data he sent him was a backup program for Zero, and that Zero does not have to be killed and can be turned to good. Finish everything, then the professor will appear and say that he has created a new life virus, and will soon hack into the world's networks, take over the missile computers, and kill everyone. Chaud and Lan will jack out. Read the e-mail you get, and Zero will give you his Z-Sabe. He will also give you his own Navi chip. Once you get it, it cannot be duplicated and you cannot fight him in the Net Battle Simulator. You can call him out, giving the enemy three good slashes and a lot of health taken away.

Get Gravity Man:
While on your way to the Zero Account, you will discover many tough enemies, including Gravity Man. This Navi can be very difficult to defeat. Make sure that you have at least a few Half Energy Subchips (useful when low on health). Also, make sure to have a lot of projectile weapons, such as Cannon, Hi Cannon, Shotgun, etc. When you begin to fight him, you will find that his main weapon are energy balls. To dodge these, jump up and down. You will switch between standing on the ceiling and ground. Then, when the time is correct, use a projectile weapon. If your health gets low, use a Half Energy.

Get Proto Man:
Have an MP count of at least 200 and set the DropDown chip as your regular chip, which you can find in Zero Account. Use the chip immediately and shoot Protoman with your Megabuster (which should be fully upgraded by now). Do not charge your gun too often, and rely more on the single shot blasts. Use DropDown again if it wears off. Use MP charges if you run out of MP and try to get a full stock of DropDown.

Get Ice Man:
Ice Man is a water type Navi. Buy three Electric Blades and use them on Ice Man. If you miss one, you are out of luck. To be safe, buy more than three.

Get Fire Man:
Have Water attacks and plenty of Swords. First, weaken him with Aqua attacks. Next, use a Sword attack. The moment you use it, jump backwards and dodge his body flame. Do this rapidly and win the battle 2 by 4.

First, destroy a lot of viruses in Lan's computer. Jack in and out several times until you have 3,000 Zenny. Go to Higsbie's store and buy at least two AquaSwrds (three recommended).

Color Man Navi secret attribute
The Color Man Navi chip has an added effect when used against enemies with barriers. When used, it instantly deactivates any elemental shield, including Bass' and the Life Virus', as well as any other elemental-barriered enemy. Proto Man also has this unique ability.

Get Sword Man:
When Sword Man is just standing there, fight with Sword chips. It will good damage, or if you do the P.A. with Ice, Fire, and Electric Sword it will do more damage. Watch out tor his swords. They will spin around for a moment, then come at you. Try to dodge them. Also watch out, as he gets up in the air. He will hover around wherever you go. He will come down quickly and do a shockwave while on the ground. Jump when he does this.

Getting Navi Chips
If you go into your Net Battle Simulator, do not battle using any Navi. Instead, use your regular Battle Chips, Restore Chips. and Mega Buster to win. This works best when your Attack and Charge are all powered up fully.